 ;; we need these values to appropriately map between meters and pixels
 ;; on the subdivided grid.
 
-(defn latlon-rad->sinu-xy
-  "Returns the sinusoidal x and y coordinates for the supplied
-  latitude and longitude (in radians)."
-  [lat lon]
-  (scale rho [(* (cos lat) lon) lat]))
-
-(defn latlon-deg->sinu-xy
-  "Returns the sinusoidal x and y coordinates for the supplied
-  latitude and longitude (in degrees)."
-  [lat lon]
-  (apply latlon-rad->sinu-xy
-         (map #(Math/toRadians %) [lat lon])))
-
 ;; These are the meter values of the minimum possible x and y values
 ;; on a sinusoidal projection. The sinusoidal projection is quite
 ;; deformed at the corners, so we compute the minimum x and y values

        lon (/ x (* rho (cos lat)))]
    (map #(Math/toDegrees %) [lat lon])))

(def
  ^{:doc "Returns the latitude and longitude for the centroid of the
  supplied MODIS tile coordinate at the specified resolution."}
  modis->latlon
  (comp (partial apply sinu-xy->latlon)
        modis->sinu-xy))


                 (dir start magnitude))]
    (map travel [+ -] [min-x max-y] [mag-x mag-y])))

;; ### Inverse Sinusoidal Projection
;;
;; We'll stay in degrees, here. To convert from MODIS to (lat, lon),
